On CT imaging, which pattern is commonly seen in severe COVID-19?

• A. Bilateral peripheral ground-glass opacities
• B. Lobar consolidation of a single lobe
• C. Pleural effusion with mediastinal shift
• D. Cavitary lesions in the lungs

Answer: (A)

Recognizing the typical CT pattern of COVID-19 is the key idea: it most often shows bilateral, peripheral ground-glass opacities due to viral pneumonitis with inflammation and partial airspace filling.

This pattern is the best match for severe disease because the process tends to affect both lungs and has a subpleural, peripheral distribution, frequently involving the lower lobes. Ground-glass opacities reflect partial alveolar filling and interstitial thickening from the viral inflammatory response, and they can progress to mixed areas of GGO and consolidation as severity increases.

Lobar consolidation in a single lobe points more toward a bacterial pneumonia. Pleural effusions with mediastinal shift are not typical in COVID-19 and usually indicate larger effusions or other processes. Cavitary lesions are not characteristic and would suggest alternative etiologies such as bacterial abscesses, tuberculosis, or fungal infections.